Biology STAAR Flashcards
(178 cards)
1
Q
activation energy
A
energy needed to start a chemical reaction; lowered by enzymes
2
Q
active transport
A
movement of molecules across a membrane requiring energy to be expended by the cell
3
Q
adaptation
A
inherited characteristic that increases an organism’s chance of survival
4
Q
allele
A
the different forms of a gene; could be dominant or recessive
5
Q
amino acid
A
basic building blocks of proteins
6
Q
analogous structures
A
structures that do not have a common evolutionary origin but are similar in form or function
7
Q
anaphase
A
the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles
8
Q
antibiotic
A
compound that blocks the growth and reproduction of bacteria
9
Q
archaea
A
domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan
10
Q
ATP
A
a nucleotide that stores and transfers energy within cells
11
Q
autotroph
A
organism that can capture energy from sunlight or chemicals and use it to produce its own food; also called a producer
12
Q
bacteria
A
domain of unicellular prokaryotes that have cell walls containing peptidoglycans
13
Q
bacteriophage
A
virus that infects bacteria
14
Q
base deletion
A
mutation which results in the loss of nucleotide pairs in a gene; have a major effect on the resulting protein
15
Q
base insertion
A
mutation which results in the addition of nucleotide pairs in a gene; have a major effect on the resulting protein
16
Q
base-pair substitution
A
a type of point mutation where one nucleotide and its partner are replaced by another pair of nucleotides
17
Q
behavioral adaptation
A
an inherited behavior that helps an organism survive; like escaping from predators or find a mate
18
Q
binary fission
A
asexual reproduction in prokaryotes by which one cell divides into two identical cells
19
Q
binomial nomenclature
A
Classification system in which each species is assigned a two-part scientific name including the genus and species
20
Q
biodiversity
A
the variety of different species in a given area
21
Q
biogeochemical cycle
A
process in which elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another; like the carbon and nitrogen cycle
22
Q
biomass
A
the total amount of living matter within a given trophic level
23
Q
capsid
A
the outer covering of protein surrounding the nucleic acid of a virus
24
Q
carbohydrate
A
organic compound used by cells to store and release energy; composed of carbon, hydrogen, and oxygen
25
carbon cycle
the organic circulation of carbon from the atmosphere into organisms and back again
26
carnivore
a consumer that only eats other consumers
27
catalyst
substance that speeds up the rate of a chemical reaction; like an enzyme
28
cell
basic unit of life
29
cell cycle
the cycle of growth and reproduction of a cell, consisting of interphase (g1, s, g2) and mitosis (division of the nucleus-prophase, metaphase, anaphase, and telophase) and cytokinesis (division of cytoplasm)
30
cell division
the process by which a cell divides into two new daughter cells
31
cell membrane
The lipid bilayer that forms the outer boundary of the cell
32
cell wall
a rigid structure that surrounds the cell membrane and provides support to the cell; made of carbohydrates
33
cellular respiration
process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
34
centriole
organize the spindle fibers to separate chromosomes during animal cell mitosis
35
centromere
area where the chromatids of a chromosome are attached
36
chlorophyll
green pigment in plants that absorbs light energy used to carry out photosynthesis
37
chloroplast
organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy
38
chromatid
one of two identical "sister" parts of a duplicated chromosome
39
chromosome
condensed threads of genetic material formed from chromatin as a cell prepares to divide
40
cladogram
diagram showing evolutionary relationships of organisms with a common ancestor; resembles a tree
41
climax community
a relatively stable long-lasting community reached in a successional series
42
codon
in RNA, a three-base "word" that codes for one amino acid
43
commensalism
symbiotic relationship in which one member of the association benefits and the other is neither helped nor harmed
44
comparative embryology
study of multicellular organisms as they develop from fertilized eggs to fully formed organisms. shows how organisms are related by evolution.
45
competition
the struggle between organisms to survive in a habitat with limited resources
46
concentration gradient
difference in concentration of a substance on two sides of a membrane
47
consumer
an organism that obtains energy by feeding on other organisms
48
crossing over
exchange of genetic material between homologous chromosomes during prophase I of meiosis
49
cytokinesis
division of the cytoplasm
50
cytoplasm
a jellylike fluid inside the cell in which the organelles are suspended
51
decomposer
organism that breaks down and obtains energy from dead organic matter
52
differentiation
process in which cells become specialized in structure and function
53
diffusion
the process by which molecules move from an area of higher concentration to an area of lower concentration; passive
54
dihybrid cross
genetic cross using two traits with two alleles each
55
diploid number
cell condition in which two of each type of chromosome are present
56
disturbance
A discrete event that disrupts an ecosystem or community. Examples of natural disturbances include fires, hurricanes, tornadoes, droughts, and floods. Examples of human-caused disturbances include deforestation, overgrazing, and plowing.
57
DNA
deoxyribonucleic acid, the material that contains the information that determines inherited characteristics
58
domain
Most inclusive taxonomic category; larger than a kingdom
59
dominant
trait that will show up in an organism's phenotype if gene is present
60
double helix
two strands of nucleotides wound about each other; structure of DNA
61
ecological succession
gradual change in living communities that follows a disturbance
62
ecosystem
living and nonliving things in an environment, together with their interactions
63
egg
Female sex cell
64
embryo
organism in its early stage of development
65
endoplasmic reticulum
a system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids
66
energy pyramid
a diagram that shows the amount of energy that moves from one feeding level to another in a food web
67
enzyme
protein that speeds up a chemical reaction
68
equilibrium
When the concentration of a solute is the same throughout a solution
69
eukaryote
A cell that contains a nucleus and membrane bound organelles
70
evolution
the gradual change in a species over time
71
experiment
the act of conducting a controlled test or investigation
72
facilitated diffusion
movement of specific molecules across cell membranes through protein channels; passive transport
73
fertilization
the joining of a sperm cell and an egg cell
74
fever
a rise in the temperature of the body
75
fitness
the ability of an individual to survive and reproduce in its specific environment
76
food chain
a series of steps in which organisms transfer energy by eating and being eaten
77
food web
a diagram that shows the feeding relationships between organisms in an ecosystem
78
fossil
the remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil
79
gamete
egg or sperm sex cell that contains a single set of chromosomes (haploid), one from each homologous pair
80
gene
sequence of DNA that codes for a protein and thus determines a trait
81
gene flow
movement of alleles into or out of a population due to the migration of individuals to or from the population
82
gene pool
all of the alleles in all the individuals that make up a population
83
genetics
the branch of biology that studies heredity and variation in organisms
84
genome
the complete genetic material contained in an individual
85
genotype
genetic makeup of an organism; like BB, Bb, or bb
86
genus
taxonomic group containing one or more species
87
golgi body
a structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and transports them out of the cell
88
gradualism
a model of evolution in which gradual change over a long period of time leads to biological diversity
89
guard cell
Pairs of cells that surround stomata and control their opening and closing.
90
habitat
the place where an organism lives
91
haploid number
half the normal number of chromosomes; found in sex cells
92
herbivore
consumer that eats only producers; also called a primary consumer
93
heritable variation
difference between organisms (tall flower) that can be passed down between generations and may affect natural selection
94
heterozygous
having two different alleles for a trait
95
homeostasis
process by which organisms maintain a relatively stable internal environment
96
homologous chromosomes
Chromosomes that are similar in size, shape, and genetic content
97
homologous structures
Structures in different species that are similar because of common ancestry.
98
homozygous
having two identical alleles for a trait
99
hypertonic
when comparing two solutions, the solution with the greater concentration of solutes
100
hypotonic
when comparing two solutions, the solution with the lesser concentration of solutes
101
independent assortment
the random distribution of the pairs of genes on different chromosomes to the gametes
102
infectious disease
A disease that is caused by a pathogen and that can be spread from one individual to another.
103
instinct
a behavior that an organism inherits
104
isotonic
when the concentration of two solutions is the same
105
kingdom
large taxonomic group, consisting of closely related phyla
106
lipid
macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes
107
lysosome
cell organelle filled with enzymes needed to break down certain materials in the cell
108
macromolecule
any large complex organic molecule
109
meiosis
Cell division that produces reproductive cells in sexually reproducing organisms
110
metaphase
second phase of mitosis, during which the chromosomes line up across the center of the cell
111
mitochondria
cellular organelles where cellular respiration occurs
112
mitosis
part of eukaryotic cell division during which the cell nucleus divides
113
monohybrid cross
a cross in which only one characteristic is tracked
114
mutagen
physical or chemical agent that causes mutations
115
mutation
change in a DNA sequence that affects genetic information
116
mutualism
symbiotic relationship in which both species benefit from the relationship
117
natural resource
materials found in nature that are used by living things
118
natural selection
process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
119
negative feedback
mechanism of homeostasis that tends to stabilize a process by reducing its rate or output
120
niche
the status of an organism within its environment and community (affecting its survival as a species)
121
nitrogen cycle
the transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere
122
nuclear membrane
controls what goes in and out of the nucleus
123
nucleic acid
a long chain of smaller molecules called nucleotides; DNA and RNA
124
nucleotide
monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base
125
nucleus
a part of the cell containing DNA responsible for growth and reproduction
126
omnivore
organism that obtains energy by eating both plants and animals
127
organ
a collection of tissues that carry out a specialized function of the body
128
organ system
group of organs that work together to perform a specific function
129
organelle
a tiny cell structure that carries out a specific function within the cell
130
organism
a living thing that has (or can develop) the ability to act or function independently
131
osmosis
diffusion of water through a selectively permeable membrane
132
parasitism
symbiotic relationship in which one organism lives in or on another organism (the host) and consequently harms it
133
passive transport
The movement of materials through a cell membrane without using energy
134
phenotype
physical characteristics of an organism; like green eyes, bushy tail or sleek tail
135
phloem
the vascular tissue through which food moves in plants
136
photosynthesis
process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and carbohydrates
137
pioneer species
first species to populate an area during primary succession
138
predation
an interaction in which one organism captures and feeds on another organism
139
primary consumer
consumer that feeds directly on producers
140
primary succession
the series of changes that occur in an area where no soil or organisms exist
141
producer
an organism that can make its own food
142
prokaryote
A unicellular organism that LACKS a nucleus and membrane bound organelles
143
prophase
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
144
protein
macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes
145
protein synthesis
the formation of proteins by using information contained in DNA and carried by mRNA
146
protist
single-celled or simple multicellular eukaryotic organisms that generally do not fit in any other kingdom
147
recessive
The inherited characteristic often masked by the dominant characteristic and not seen in an organism.
148
replication
(genetics) the process whereby DNA makes a copy of itself before cell division
149
reproductive isolation
separation of species or populations so that they cannot interbreed and produce fertile offspring
150
response
a bodily process occurring due to the effect of some stimulus or agent
151
ribosome
An organelle that functions in the synthesis of proteins
152
RNA
ribonucleic acid; a nucleic acid that plays an important role in the production of proteins
153
secondary consumer
consumer that eats primary consumers
154
secondary succession
succession following a disturbance that destroys a community without destroying the soil
155
selectively permeable
a property of cell membranes that allows some substances to pass through, while others cannot
156
somatic cell
Any cell in a multicellular organism except a sperm or egg cell.
157
speciation
the formation of new species as a result of evolution
158
species
taxonomic group whose members can interbreed
159
stimulus
a signal to which an organism responds
160
stomata
Small openings on the underside of a leaf through which oxygen and carbon dioxide can move.
161
structural adaptation
a physical feature of an organism's body having a specific function that contributes to the survival of the organism
162
substrate
The reactant on which an enzyme works.
163
symbiosis
relationship in which two species live closely together
164
taxonomy
a classification of organisms into groups based on similarities of structure or origin etc
165
telophase
the final stage of meiosis when the chromosomes move toward opposite ends of the nuclear spindle
166
theory
well-tested explanation that unifies a broad range of observations
167
tissue
group of similar cells that perform a particular function
168
toxin
a poison that can harm an organism
169
trait
a characteristic that an organism can pass on to its offspring through its genes.
170
transcription
process where the DNA sequence in a gene is copied into mRNA
171
translation
decoding of a mRNA message into a polypeptide chain
172
transpiration
loss of water from a plant through its leaves
173
trophic level
feeding level in an ecosystem
174
vaccine
substance prepared from killed or weakened pathogens and introduced into a body to produce immunity
175
vacuole
cell organelle that stores materials such as water, salts, proteins, and carbohydrates
176
virus
package of nucleic acid wrapped in a protein coat that must use a host cell's machinery to reproduce itself
177
xylem
the vascular tissue through which water and nutrients move in plants
178
zygote
fertilized egg
